1. Field of the Invention
The present invention relates to an antenna apparatus, and more particularly, to an antenna apparatus which accommodates a small flat antenna module and which is mounted on external equipment.
2. Description of Related Art
In recent years, there are small flat antennas which have been developed as antennas used for GPS car navigation systems, portable navigation systems, satellite wave receivers and the like.
The differences occur in performance of an antenna depending upon a mounting position and a mounting angle. Therefore, in order to operate an antenna normally, the mounting mechanism thereof is important. Especially in the case of an antenna used for a vehicular GPS system, it is necessary to dispose the antenna horizontally in a vehicle. Thus, when a vehicular GPS system is configured, the mounting mechanism of a GPS antenna is important.
In this regard, conventionally, a unit module in which an antenna (antenna module) and a high frequency circuit substrate which performs processings such as removing the noise from received radio waves and amplifying the waves combined together and unitized, is accommodated in a resin case also comprising a top cover and a bottom cover. Generally, the bottom cover is fixed to a metal mounting bracket, and this metal bracket is mounted on a dashboard or the like of a vehicle.
However, when the case comprises the top cover and the bottom cover and the bottom cover side is fixed to the metal bracket, there is a problem that the number of parts is increased and thus, the number of assembling steps is increased. Therefore, the apparatus cost is increased.
Hence, the antenna apparatus is devised so that a unitized GPS antenna is accommodated in a cover member comprising a GPS antenna container, a mounting section to be mounted on the metal bracket is provided, and the cover member side is fixed to the metal bracket. Therefore, the antenna is mounted (see patent Japanese Patent Application Laid-open Publication No. 11-74716 for example).
However, since the metal bracket does not have flexibility, in order to mount the antenna horizontally, it is necessary to carry out adjustment to previously bend the antenna in accordance with a shape of a portion to be mounted on the antenna, or to sandwich another member between the cover and the metal bracket on the mounting side. Further, in a case of the metal bracket, when a screw hole for mounting the metal bracket on a vehicle body is formed, the screw hole can only be formed vertically, and the freedom degree in design of the metal bracket is low. Therefore, there is a problem that a plurality of kinds of metal brackets are required to be prepared in accordance with a shape of the receiving side, and the development cost is increased.